I found Vault Pro USA mentioned in a magazine and was amazed that their products, which could be either a huge gun vault or a small FEMA shelter, is using a modular construction that could be added to an existing structure, be standalone, and could be conceivably expanded in the future, unlike standard safes. The cost is the same as a large safe, but it seems to offer much more. Has anyone either bought this product, or witnessed it in person? What is the quality, fit and finish like? Really curious if it's as strong as it looks and as easy to assemble as they say.